Various types of ball screw nuts are known. Among types of such nuts in addition to tube ball-return types may be mentioned 20th Century, Flopover, Starr, Cincinnati, and Jena-Tec models. Among drawbacks to such nuts can be their high unit cost, high installation cost, lack of adaptability to various ball screws or machinery therewith, quick rate of wearing out and/or practical inability or economic unviability to repair some models. Compare the following patents or patent application publications:    Brunthaver, U.S. Pat. No. 477,642 (Jun. 28, 1892);    Coughlan, U.S. Pat. No. 611,832 (Oct. 4, 1898);    Boehm, U.S. Pat. No. 1,704,031 (Apr. 11, 1927);    Means, Jr., U.S. Pat. No. 2,380,662 (Jul. 31, 1945);    Cole, U.S. Pat. No. 3,053,105 (Sep. 11, 1962);    Miller, U.S. Pat. No. 4,638,548 (Jan. 27, 1987);    Miller, U.S. Pat. No. 4,760,635 (Aug. 2, 1988);    Schlenker, U.S. Pat. No. 4,953,419 (Sep. 4, 1990);    Schlenker, U.S. Pat. No. 5,063,809 (Nov. 12, 1991);    Namimatsu et al., U.S. Pat. No. 5,493,929 (Feb. 27, 1996);    Kobayashi et al., U.S. Pat. No. 5,653,145 (Aug. 5, 1997);    Lee, U.S. Pat. No. 5,791,192 (Aug. 11, 1998);    Misu, U.S. Pat. No. 6,176,149 B1 (Jan. 23, 2001);    Greubel, U.S. Pat. No. 6,425,302 B2 (Jul. 30, 2002);    Nagai et al., U.S. Pat. No. 6,446,520 B1 (Sep. 10, 2002);    Ohkubo, Pub. No. US 2006/0137485 A1 (Jun. 29, 2006);    Liao et al., Pub. No. US 2007/0186708 A1 (Aug. 16, 2007);    Hsu, U.S. Pat. No. 7,516,681 B2 (Apr. 14, 2009);    Chen, U.S. Pat. No. 7,520,193 B2 (Apr. 21, 2009);    Pan et al., U.S. Pat. No. 7,523,681 B2 (Apr. 28, 2009); and    Liao et al., U.S. Pat. No. 7,523,682 B2 (Apr. 28, 2009).Of the patents or patent application publications, Chen, and Lee, Misu, Greubel and Pan et al. may be of greater possible interest.
It would be desirable to ameliorate if not solve one or more of such drawbacks. It would be desirable to provide the art with an alternative.